See primary documentation in context for routine snapper
sub snapper( = 0.1, :, : --> Nil)
snapper routine starts a separate thread that will call
snap repeatedly until the end of program. It is exported by default.
By default, it will call
snap every 0.1 second. The only positional parameter is taken to be the delay between
Please see the snapper module for externally starting a snapper without having to change the code. Simply adding
-Msnapper as a command line parameter, will then start a snapper for you.